1207 Silicosis, especially complicated, shows significant lung volumes and airflows impairment compared to interstitial lung diseases of non-occupational aetiology

Abstract

Introduction Silicosis belongs to the interstitial lung diseases, a heterogeneous group of many diseases of a different aetiology. Common symptom of all these diseases is dyspnoea. Lung function tests usually show restrictive defect with decreased diffusion capacity (DLCO). However, the heterogeneity of these diseases brings a question, if silicosis, a typically occupational disease, differs from other non-occupational interstitial diseases in the pathogenesis of symptoms and lung function impairment. The aim of study was comparison of lung functions in patients with silicosis and non-occupational interstitial lung diseases. Methods In total, 30 patients with simple silicosis, 32 patients with complicated silicosis and 30 patients with non-occupational interstitial lung diseases underwent spirometry, bodypletysmography and DLCO examination. We compared vital capacity (VC), forced expiratory volume in one second (FEV 1 ), FEV1/VC ratio (Tiffeneau index), total lung capacity (TLC), residual volume (RV) and DLCO between these 3 groups of patients. Results Vital capacity was more decreased in silicosis, both simple and complicated compared to the non-occupational interstitial lung diseases (p Discussion Study confirmed differences in the pathogenesis of symptoms in silicosis and patients with non-occupational interstitial lung diseases. Apparently, in the case of simple silicosis, the symptoms are the result of bronchial obstruction without severe lung parenchyma destruction. In the case of non-occupational interstitial lung diseases, a predominant sing was decreased DLCO as a result of alveolocapillary membrane impairment without significant changes in lung volumes and airflows. However, complicated silicosis was characterised by significant volumes and airflows impairment and lung hyperinflation with decreasing DLCO.